function supports_video(){
	return !!document.createElement('video').canPlayType;
}	

function supports_video_mpeg4(){
	if(supports_video()){
		var v=document.createElement('video');
		return v.canPlayType('video/mp4; codecs="mp4v.20.8"');
	}
	return ""
}

function supports_video_webm(){
	if(supports_video()){
		var v=document.createElement('video');
		return v.canPlayType('video/webm;codecs="vp8,vorbis"');
	}
	return ""
}

function supports_video_h264(){
	if(supports_video()){
		var v=document.createElement('video');
		return v.canPlayType('video/mp4;codecs="avc1.42E01E,mp4a.40.2"');
	}
	return ""
}

function supports_video_theora(){
	if(supports_video()){
		var v=document.createElement('video');
		return v.canPlayType('video/ogg;codecs="theora,vorbis"');
	}
	return ""
}

function supports_video_poster(){
	return 'poster' in document.createElement('video');
}

function supports_video_track(){
	return 'track' in document.createElement('track');//��Ļ
}

function supports_video_autoplay(){
	return 'autoplay' in document.createElement('video');
}
///���ز��˰ɣ�����ȫ��֧�ֵ�����
/////

function start_video_test(container) {
	console.log(container);
	htmlContent = "Video Element: " + (supports_video() ? " yes" : " no") + "<br/>";
	htmlContent += "Subtitle Support:" + (supports_video_track() ? " yes" : " no") + "<br/>";
	htmlContent += "Poster Image Support:" + (supports_video_poster() ? " yes" : " no") + "<br/>";
	htmlContent += "MPEG-4 Support:" + (supports_video_mpeg4()!="" ? " yes" : " no") + "<br/>";
	htmlContent += "H.264 Support:" + (supports_video_h264()!="" ? " yes" : " no") + "<br/>";
	htmlContent += "Ogg Theora Support:" + (supports_video_theora()!="" ? " yes" : " no") + "<br/>";
	htmlContent += "WebM Support:" + (supports_video_webm()!="" ? " yes" : " no") + "<br/>";
	
	container.html(htmlContent);
}

